Devices for injecting fuel or other media into internal combustion engines



W. B. SKIPPER NJ Nov 24, 1959 OR OTHER MEDIA TION ENGINES DEVICES FOR IECTING FUEL INTO INTERNAL COMBUS Filed Nov. 1,

r 0 t n e U n I I i WILLIAM BURKE SK/HOER md F o 12 in the distributor.

United States Pater-1t Claims priority, application Great Britain`November 15, 1955 v This invention` relates to'devices forinjectingfuels (either of the lubricating kind or not) or other media suchasanti-detonates `into internal combustion engines.

Devices forthis purposehave been proposed in which at least one deliveryconduit and at least one pressure provision is made for chargingthe.-delivery conduit with a constantwquantity of fuel or. other` liquid(hereinafter referred ,to as fuel). at each return stroke of thepartition and for usefully discharging the fuel on the forward strokesof the partition in proportions that can be manually varied.

An object of the present invention is to provide new and improved meansfor metering theffuel deliveries in a manually variable manner whichenables the number of the moving parts of the device to be considerablyreduced. l

ln accordance with the invention the device includes a distributorrotatable in the body of the device for controlling the periodic supplyand discharge of pressure liquid to and from the or each pressure liquidchamber, a return llow passageway in the distributor for the presl sureliquid, and a manually operable valve'controlling the outlet from thepassageway thereby to vary each return stroke of the movable partitionwhich is preferably a movable piston and thus variably meters thequantity of fuel admitted on such stroke to the fuel delivery conduit.

By way of example one form of injection device in accordance with theinvention is shown diagrammatically on the accompanying drawings.

Fig. l represents this form as a composite, longitudinal section on l-Iof Fig. 2.

Fig. 2 represents a half end view and a half section in the plane ll-llof Fig. l.

Fig. 3 represents a cross section in the plane III-Ill of Fig. l.

The same references are used throughout to denote the same or similarparts.

The body of the injection device comprises the two parts 1 and 2detachably held together by stud bolts 3. Body part 2 isvprovided with afuel inlet nipple 4 (shown only in Fig. l); with fuel outlet nipples 5,one for each engine cylinder, there being six in the present examplewhich is intended for a sixcylnder, internal combustion engine; and withan inlet nipple 6 for a high pressure pumping liquid, and a return oroutlet nipple 7 for this liquid.

Rotatably mounted in an axial bore 8 of the body part 2 there is adistributor 9 for the pumping liquid, this distributor having an annulus10 in constant communication with the inlet nipple 6 via a duct 11 inthe body part 2. An axial duct or passageway 41a in the distributor hasan enlarged portion 42a at one end of the distributor. Annulus lcommunicates with a duct A manually operable control rod 14 projectsthrough a small bore in one end of the body `liquidc'hamber areseparated by a movable partition, and v `fluted stem.

2,913,986 Patented Nov. 24, ,1959

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. 2 Y part 2 into the bore 8, its inner end being formed as restriction14a that co-acts with said larger portion 42a leading to .passageway 41ato control'the rate of return ow of liquid via a duct 42 and the returnnipple 7. The other end of the distributor 9 has a shaft 16 rotatablymounted in the body part 1.

Extending through the body part 2 in line with each fuel outlet nippleis a bore 22. In each such bore 22 there is`a liner or barrel 23affording a fuel delivery con duit 24 open to an annulus 25 via radialducts or passage- Ways 26, andy housing a non-return valve 27' which isbiased to its closed position by a spring 28 and which, when open,places the conduit 24 in communication with the pertaining fuel outletnipple. Each valve 27 has a A freely oating piston or partition 37within each liner or barrel 23 separates the fuel delivery duct 24 froma pressure liquid chamber 38 at the rear of the floating piston.` Whenthe distributor 9 is'rotated, the pressure liquid chambers 38 areplaced, in turn in communication with' the duct .f12.of the distributorby means of radial ducts 39(Figs; 1 and-3). These radial ducts 39 also`cotrnnunicate infturn with a radial duct or passageway 40a in thedistributor leading via the axial duct 41a `and enlarged portions 42aand duct 42 back tothe outlet or return nipple 7.

The beforementioncd fuel inlet nipple 4 (Fig. 2) communicates with afuel gallery 43 formed in the body part 2, this fuel gallery in turncommunicating with the inlet chambers 44 (Fig. 1) of six fuel inletvalves each comprising a valve housing 45 screw-threaded into acorresponding bore in the housing part 2, and a tinted-stemmed valvemember 46 biased to its seat in the valve housing by a spring 47. Thebore containing this spring constitutes the outlet bore of thecorresponding fuel inlet valve; it communicates by a branch 48 (shownonly in Fig. 3) with the annulus 25 of the pertaining fuel conduit 24.

The inlet nipple 6 communicates, via a conduit, with an accumulator (notshown) supplied with liquid at high pressure by a suitable pump (such asthe well known Deri pump); and the outlet or return nipple 7communicates via a conduit with a sump or reservoir (not shown) fromwhich liquid is supplied to the pump. Be tween the pump and thereservoir there is an over-pressure, spring-load relief valve to ensuresubstantially constant pressure of the liquid in the accumulator.

In practice the described device is suitably mounted on the engine andthe shaft 16 is arranged to be driven from the engine at half the speedof the engine crankshaft in the case of a four-stroke cycle engine. Fuelis supplied to the fuel inlet nipple 4 by a low-pressure pump (notshown) driven by the engine, as is the pump for the supply ofhigh-pressure pumping liquid.

It will be evident that fuel from the gallery 43 will tlow past thenon-return valves 46 and via the bores 47 and ducts 48, 25, 26 to thoseof the fuel delivery conduits 24 in which the rear of the oating pistons37 are not for the time being subjected to high pressure pumping uid,the fuel forcing back the floating pistons 37 in those conduits 24against their abutments 32a. High pressure liquid from the aforesaidaccumulator will ow, via the nipple 6 and duct 11 and annulus 10 to theduct 12 in the distributor 9. As 4this duct is brought to register witheach radial duct .39 the high pressure liquid exerts pressure in thepertaining pressure fluid chamber 38 on the rear of the correspondingfloating piston 37, whereby this piston is urged to the right in Fig. 1forcing the fuel content of the conduit 24 past the non-return valve 27to the pertaining fuel outlet nipple and thence to the fuel injector ofthe corresponding engine cylinder. The liquid pressure in the pressurechamber 38 is relieved when, on Con.-

tiouod rotation of the distributor 9, said faail doom9 is .placed incommunication with the radial duct 40a leading passage portion 42a forthe return flow of the .pumping liquid past the valve-like restriction14a to a variable extent, thereby correspondingly varying the xtentofbackward movement of the pistons 37 and consequently fthe amount of fueladmitted to the fuel conduits 24.

It will be seen that with the described arrangementfor metering thequantity of fuel the number of moving Lparts per fuel outlet is reducedto the minimum.

Clearances of the Working parts is not critical since .leakage past themdos not aiect the fuel metering.

Only small driving torque is necessary and this isfcoriJ The device canbe made quite small in size and isfcapable of operation at speeds highenough 'for two stroke cycle as well as four stroke cycle internallcombustion engines.

I'claii:

A device for injecting fuel into an internal combustion engine,comprising a body having at least one delivery conduit, at least onepressure liquid chamber, a movable partition separating the deliveryconduit and the pressure liquid chamber from one another, passageways inthe body including a non-return yvalve for supplying fuel under lowpressur'eto .the delivery conduit, a vnon-rettifrn'valve controlling theoutlet from the delivery conduit, a distributor rotatable in the bodyfor controlling the periodic supply and discharge of a pumpingliquid athigh -pressure to and from the pressure liquid chamberiareturn'owpassageway in the distributor for the pressure liquid, and a manuallyoperable valvejcontrolling the outlet from said passageway thereby tolimit each return stroke of the movable partition and Avariablfyv meterthe quantity of fuel admitted on such stroke'to 'the 'delivery conduitprior to the expulsion of said fuel by the next forward stroke of saidpartition under the action of the high pressure pumpving liquid admittedto the high, pressure liquid chamber.

References ACited in the file of this `patent UNITED STATES PATENTSy2,406,296 Ield Allg. 20; 1946 2,484,884 Hanna Oct. 18,A 1949 2,531,332.Garday Nov. 2l, 1950 2,698,580 Evans Jan. 4, 1955 i i i i l t

